Redskins tackle Jordan Black was suspended yesterday without pay for four games for violating the NFL’s policy on performance enhancing substances, the team’s sixth drugs-related suspension in less than two seasons.

Black’s suspension began immediately and will include postseason games if the Redskins advance to the playoffs.

Washington left tackle Trent Williams, tight end Fred Davis and cornerback Phillip Buchanon all received four-game suspensions from the league last year. Safety Tanard Jackson was suspended for the season this year, and Cedric Griffin is serving a four-game suspension.

Meanwhile, coach Mike Shanahan said he’s still waiting for a thumbs-up from the doctors before declaring that Robert Griffin III (knee sprain) can return to game action.

“We’re going to play Robert when he’s 100 percent,” Shanahan said.

COWBOYS: Team owner Jerry Jones and coach Jason Garrett were unaware of John Brent’s attendance on the sidelines until Sunday’s game against the Steelers was about to begin.

Brent, on the non-football injury list after being involved in a car accident that killed teammate Jerry Brown, came to the game at the urging of his teammates, a source said.

When Brent became aware that his appearance was causing a debate, he left in the second half.

BROWNS: Defensive back Dimitri Patterson was waived after appearing in seven games this season with four starts.